I've just come across a new website that will turn RSS feeds into an ebook. It's called, appropriately enough, NEWSTOEBOOK. You can use it to make Epub or Mobi ebooks from almost any RSS feed, and soon you'll be able to gather tweets, too.
BTW, Feedbooks used to provide a similar ability, but they stopped for some reason. I'm glad I found a replacement.
I've tried this with a couple blogs, and for the most part it works well. The ebooks are well formatted, there's a TOC, and in general it's a decent read. But there are a couple not so good points. All the images were converted to grayscale, and there was no need for that. I'm reading it on a laptop, so the lack of color was a disappointment. Also, I looked but did not see a self update button built in to the ebook. That would have been nice to have.
But it's only fair that I point out that NEWSTOEBOOK is still under development, and I'm sure it will improve as time goes by. If it ever gets to the point where I don't have to go back to the website each time, it's going to be very useful.